Orthodontics involves the movement of teeth through bone. By applying pressure to a tooth, bone can be broken down at a leading edge of the tooth to facilitate tooth movement. New bone is then created at a trailing edge of the tooth. Bone is resorbed in (e.g., broken down) in areas of pressure between a tooth root and periodontium, and bone is deposited (created) in areas of tension between a tooth root and periodontium. Pressure can cause resorption and tension can cause deposition regardless of where they occur along a tooth root surface. Movement of teeth through bone is slow based on the speed of the remodeling process while teeth are undergoing conventional orthodontic treatment, thereby necessitating treatments of long duration in order to achieve the desired tooth position. Tooth movement in adults is slower than tooth movement in adolescents. Long-term orthodontic treatment can have an increased risk of root resorption, gingival inflammation and dental caries. Moreover, movement of teeth through bone can be uneven, as teeth might “tip” due to the force applied, i.e., the crown of the tooth can move in the desired direction more quickly than the root of the tooth, resulting in tipping of the tooth. When teeth to move “bodily” through the bone, i.e., in a more or less perpendicular orientation relative to the bone, the teeth move without tipping or with only a low degree of tipping.
Methods for increasing the rate of tooth movement without damage to the tooth and periodontium have been sought. For example, acceleration of tooth movement can be achieved by the local injection of prostaglandin, the active form of vitamin D3, and osteocalcin around the alveolar socket. These substances might increase the rate of tooth movement, but might also cause side effects such as local pain and discomfort for a patient during the process of injection. In a recent study, more than 65% of the subjects in North America have been shown to be deficient vitamin D serum levels. In these vitamin D-deficient subjects, bone metabolism and remodeling can be adversely affected.
Apparatuses useful for delivering light therapy to the dental and maxillofacial areas of a patient have been described, for example, in PCT publication numbers WO 2009/000075 and WO 2006/087633, both of which are hereby incorporated by reference in their entirety. However, there remains a need for light-therapy apparatuses that can deliver specifically targeted light therapy to flood desired regions of a patient's jawbone with light having desired characteristics.
A significant amount of malocclusion in dental patients is caused by lack of sufficient horizontal or vertical growth of the mandibular bone. This can result in the lower teeth being positioned too far in a posterior direction, leading to an increased overjet and retrusive chin. In some situations, the mandibular bone can be too far forward or backward, and it can be desirable to move or remodel the mandibular bone. In other situations, it can be desirable for the maxillary bone to be remodeled.
Typical treatments involve surgical advancement or dental compensatory orthodontic treatment. Some more recent therapy involves the functional repositioning of the mandibular bone forward using an intra-oral orthodontic appliance. This repositioning of the mandibular bone creates remodeling of the temporomandibular joint (TMJ) and also some tooth movement as compensation to the forces. The problem, however, with this approach is that it can take up to 12 months to correct the mandibular position. Additionally, such approaches appear to have much less effectiveness in adults or non-growing adolescents.
A need exists for methods and apparatuses that are useful for increasing the velocity (or rate) or improving the quality of bone remodeling. A further need exists for methods and apparatuses that are useful for increasing the velocity (or rate) or improving the quality of tooth movement through bone in response to orthodontic treatment, to decrease treatment times for patients without undesirable side effects or pain. There is also a need for methods and apparatuses that can be used to achieve a desired mode or quality of movement of teeth through the bone, e.g., bodily movement of teeth through bone, and that are adjustable to permit tooth movement to be modulated at a desired specific location or locations within a patient's jaw region.